Monday, June 27, 2016

Eli made an interesting point on Twitter (this assumes that a) Eli can make an interesting point and b) that an interesting point can be made on Twitter, but no matter) about energy mix.

The nature of the thing is that the world's electrical energy needs can be met by renewables, e.g. solar, wind and hydro, but the intermittent nature of the first two require overbuilding both the installation and the distribution network and as the complexity of the distribution network increases, so does that cost and the time needed to deploy. It can also lead to sudden surges in birthdays when the network fails.

Nuclear baseload on Eli's other hand can balance the amount of overbuilding necessary but it was pointed out that the balance requires controlling costs and reducing construction time.

12 comments:

Controlling cost and reducing construction time of nuclear are both entirely feasible (China's doing both, ditto Korea). There is no cheap answer to intermittancy of RE, other than limiting grid penetration. Wind can be cheap OR plentiful, but not both at the same time. That's because wind competes with itself, driving revenues down when it's windy, an effect that gets worse and worse as penetration increases. (Solar will always be expensive. It's just too diffuse. And before you trot out that well-worn graph of the cost of solar cells, remember that as the price of solar cells declines, more and more of the cost of solar is made up by the physical structures, which are not subject to Moore's Law.)

The fastest cheapest plan is: hydro and geothermal where available; wind up to the curtailment point; and nuclear for the rest.

By nature solar/battery micronets are easier to build and control especially in remote locations and especially in the developing world where networks are subject to outages from random weather and maurading.

Even in the developed world such micronets are coming to the fore, for example in Germany, where they allow sharing of storage capacity as an answer to what happens when net metering becomes less profitable to homeowners

I suspect (and hope) that new models for grid management (for instance, using hydro for switchable backup instead of baseload, as I believe Jacobson and Sustainable Dialogues Canada have recommended in plans for Canada), along with an upgraded grid (which offers some co-benefits...), may make this problem easier to cope with than some have assumed.

Nuclear power plants have a very slow response time. France produces highly subsidised nuclear power for all of Europe during the night. Thus also for nuclear there is a mismatch between supply and demand (with the current fixed price system).

The solution is naturally a free market with market prices. That brings supply and demand together for much more complicated product. This intriguing argument about intermittency can be made about any product; supply and demand always fluctuate.

It is funny that the self-proclaimed supporters of the free market are typically the renewable energy sceptics.

Having now finished Bryce's book, Power Hungry, I have been reminded of all the back and forth I've experienced since installing what I think to have been the first "modern" wind energy system in California over Labor Day weekend in 1973. That system employed a 3 bladed horizontal axis turbine rated at 2 kW max, feeding electricity to a bank of lead acid cells storing 40 kWHr of electricity at 120v. As I later progressed, working with others on a large study of renewables, then as a returning student at Stanford, becoming the Aero department's wind energy expert, I was repeatedly reminded that renewables are intermittent and thus need either storage systems or backup for periods during which there's no generation.

That was some 40 years ago and nothing's really changed, as Bryce described in some detail. His book does a great job of presenting his case, leading to his conclusion that we must move to a "N2N" path, as in more less coal, Nat Gas and then Nukes. He's a good writer and his book is an easy read with lots of graphs, but he manages to gloss over several important points. In the end, his prescription includes "nuclear parks" where reprocessing and generation are to be co-located, while later describing the opposite situation of many smaller scale factory built plants spread far and wide. His solution to the waste problem is to reprocess spent fuels to recover, then "burn" the high level waste, including plutonium. He also speaks to a switch to a Thorium fuel cycle, which would not result in Plutonium in the waste.

Way back when, the electric power industry was facing a growth in demand of 7% a year, thus doubling every 10 years, leading to simplistic claims for the need to build 1,000 nukes in the US by the year 2000. Didn't happen and several of the plants which had been started before Three Mile Island were later canceled as the growth rate collapsed due to steeply rising costs for electricity. Now, we see Nat Gas in such abundance that coal power plants aren't competitive and are being closed. Some of the nukes are also being closed as well, their 40 year licenses allowed to expire instead of being extended another 20 years.

Those who promote nukes have faced an uphill battle after TMI and things became worse after Chernobyl. Bryce ignored the implications of both in his book which appeared before Fukushima, a prime example of Normal Accidents and Rumsfeld's "known unknowns and unknown unknowns", which resulted in the shutdown of all of Japan's nukes. Bryce also failed to discuss the electric industry's mix of plants using base load, intermediate and peaking plants when discussing availability. Nukes are intended to supply the baseload fraction because of economics and their large thermal and fuel decay inertias. The large 1,000+ megawatt nukes can not match the demand load by themselves, thus suffer from the same sort of intermittency problem as renewables, but from the other side of the demand curve. Again, the problem is that some form of storage would be required in a total nuke world, perhaps fossil fueled gas turbines, hydro or batteries . Once the storage problem is resolved, as may be expected, the only remaining debate will be over the relative cost of the electricity from the alternatives.

About 14 years ago, the TVA proposed building a batch of large wind turbines on a nearby mountain top. The plan included storage using a "flow battery" system. The locals folks appeared at the public hearing and it was shot it down. The flow battery system was designed by a British company, Regenesys, for which the plant was? to be their pilot plant. After the plan was scuttled, the company went bankrupt and their assets (including patents?) were bought by a German utility. Another opportunity lost, perhaps, unless the Germans continued development...

A couple of commenters above have declared that nuclear plants are baseload only, and therefore cannot load-follow. This is a pernicious myth. Nuclear plants in France load-follow routinely, and nuclear plants aboard Navy ships and subs must be able to go from "all stop" to "full speed ahead" in a matter of seconds.

Nuclear power plants in the US don't load follow, but that's an economic decision, not a technological constraint. When demand falls, it makes sense to turn off the fossil plants first, since most of the cost of fossil energy is in the fuel, while fuel costs in a nuclear plant are negligible. In other words, you save money by turning off the fossil plant, but not by turning off the nuclear plant.

In fact, nuclear plants in the US can ramp at about the same speed as combined-cycle gas turbines -- which makes sense, since a turbine doesn't care where the heat comes from. Further, if the grid ever reaches a stage in which increasing renewables make nuclear load-following necessary, there are simple and cheap modifications (like adding boron to the primary coolant loop) that would make reactors even more nimble.

KAP, load following is surely an important characteristic for sub power, but the latest USS Virginia, with it's 37 megawatt reactor, will be much quicker to respond than a commercial unit rated at 1,000 megawatt electric. Then too, the military is more interested in performance than cost, as survival is paramount to complete their missions.

E. Swanson,Oh gee. Look at the big number. $21 billion. Everybody be very afraid of the big big number.

Here's another big big number: 1,057,495,200. That's the number of megawatt-hours Vogtle will produce in its 60-year lifetime. Which means that the capital expenditure of Vogtle amounts to less than 2 cents per kWh. So can you scare us all again about how expensive nuclear is? Because some of us can do the math.

Now let's do the same for solar: Topaz is 550 MW and cost $2.4 billion to build. It produces 1,300,000 MWh per year. According to NREL solar PV has a lifetime of 20 years, but we're going to say 25 years just to be overly fair. So over its lifetime it will produce 32.5 million MWh, or 7.4 cents per kWh -- more than three times the capital cost of nuclear, which you say is too high.

Yet we never hear anyone complain about the high cost of solar.

You correctly point out that nuclear can't compete with natural gas. Very true. Neither can solar, and (except for the Great Plains) neither can wind. RE gets built because of states' RPS that demand it, not because of economic need. If nuclear were included in the RPS mandate, you would see more of it being built.

KAP, it's great fun playing with a calculator, as long as one includes all the details. Your number spreads that $21B over 60 years and assumes 90% capacity factor for 2 reactors. However, aren't you ignoring the interest on the loans which provided that $21B, as well as staffing 24/7/365, 60 years of maintenance, fuel and re-fueling costs, as well as decommissioning and the dealing with the expenses related to depleted fuel? Then too, the AP1000 reactors are a new design, none of which have begun to operate.

Your estimate of a 20 year lifetime for PV appears to be too low, given that PG&E has agreed to a 25 year purchase of the power from TOPAZ and the project lifetime is 35 years. Furthermore, the Topaz project is already online, producing electric power after a construction time of 18 months without a loan guarantee from DOE.

Yes, let's talk about decommissioning costs. In Germany the power companies now transfer their nuclear power plants to separate companies, which will go bankrupt before decommissioning is done and then the tax payer can pay for the decommissioning.

Make sure this does not happen elsewhere and build up funds for decommissioning. Do not let the power companies run these funds; they will invest it in their own companies, which go bankrupt and are then not worth anything anymore.

While these people get rich on the backs of the poor, they despise them because they did not fight back. Fight back in time.

(The computation of KAP somehow did not include an insurance. Another moral hazard. Maybe because the risk is so high that no insurance company is willing to insure the meltdown of a nuclear power plant.)

I think nuclear will be impacted by the market emergent defacto carbon price that intermittent penetration brings - during periods of abundant solar and wind (in an open electricity market) other supply is forced into intermittency. Whether nuclear is capable of varying output or not it means charging more outside those periods, with, perhaps, selling below cost outside then as an anti-competitive measure, which may be illegal - unless regulators give special treatment. Such special treatment is most likely as a side effect of special treatment for fossil fuel plant. It all makes for big incentives for storage - the true value of which will be much greater than any averaged power price can reflect. Not fair perhaps, but deferring the true costs of fossil fuel use to future generations isn't fair either. We have to commit to low emissions urgently and do so ahead of certainty about how the final energy mix will be achieved, but I think fixed 'baseload' being forced into intermittency and temporary backup to renewables is a step in the right direction.

We can consider households having two or more cars as unremarkable, but a household with an investment in storage similar to one small to medium car is made to seem unacceptable. And meanwhile nuclear in many nations suffers the double political hit of the most pro-climate political forces backing renewables, whilst the main political home of support for nuclear is thoroughly overlapped with opposition to strong climate action, with that opposition looking like every day every way and support for nuclear for climate lacking credibility. The anti climate action priority is antithetical to building the strong community consensus about a 'most serious' climate problem that this 'most serious' of solutions depends upon. It does seem to retain some usefulness - as a rhetorical blunt instrument for whacking greenies and renewables with, but unfortunately (at least here in Australia) it's most likely to do so in the hands of staunch opponents of climate action, ie it comes with no actual commitment to nuclear for climate attached.

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Eli Rabett

Eli Rabett, a not quite failed professorial techno-bunny who finally handed in the keys and retired from his wanna be research university. The students continue to be naive but great people and the administrators continue to vary day-to-day between homicidal and delusional without Eli's help. Eli notices from recent political developments that this behavior is not limited to administrators. His colleagues retain their curious inability to see the holes that they dig for themselves. Prof. Rabett is thankful that they, or at least some of them occasionally heeded his pointing out the implications of the various enthusiasms that rattle around the department and school. Ms. Rabett is thankful that Prof. Rabett occasionally heeds her pointing out that he is nuts.